Tunnel-kiln



P. DH. DRESSLER.

TUNNEL'KILN.

'APPLICATION FILED MAY 28. 1919. 1,330,433.,l Patented Feb. 10,1920.

Fg' .1 *J E' ,-42" F 17 I Y l INVENTOH dud/@75,5 Huid/Mom BYu" ATTORNEYi n sraarasraanr lannion.

IHILIIl? DH. DRSSLER, OF ZANESVILLE, OHIO, ASSIGNOR TO AMERICAN DRESSLERTUNNEL KILNS, IN C., OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

i TUNNEL-Kun.

To all 'whom it may concern:

I Be Vit knownthat I, PHILIP nH.1DRESsLnR, a subject of the .KingofGreat Britain, and Y 'resident of Zanesviller'in the county of V,5Muskingum and State of Ohio, have invent- I ged certain new and usefulImprovements in -Tunnel-Kilns, of'which the following is aspecification.

Y M v present invention relates to tunnel kilns' in which 'a hightemperature zone isiuaintained in the kilns at a distance from the heador entrance end of the kiln 'and in which the portion of the kilnbetween the high temperature zone and the entrance end forms a heatingup zone through which the temperature'varies more or less graduallyfromlone end to the other. In such a kiln as the goods mounted on carsare moved slowly through the kiln from its entrance end to and throughthe high temperature l characterize my invention are-pointed out zone,the goods' are gradually brought up to the high temperature prevailingin the high temperati'ue zone.

The object' ofthe present provide 'simple and effective means wherebythe temperature graduation in the heating up zone of the kilniscontrolled, and my invention preferably comprises means whereby thetemperature in the heatingup zone of the kiln may be adjusted to meetdifferent v operating conditions.

My present invention was primarily devised as nnprovement on thewell.known Dressler tunnel kiln 4in which the high temperature zone ofthe kiln -is heated by the combustionl of gas in the combustion cham,-bers located within the kiln at the high temperature zone thereof, andin which the products ofcombustion are withdrawn from the combustionchambers proper through conduit extensions thereof passing through theheating up zone of the .kiln to' a point adjacent the head end of thekiln where these conduits are `connected-to some draft stack. In thistype of kiln the heat remaining in the products of combustion leavingthe combustion chamber proper is to a large extent radiated from thewalls of the conduit connect-ing the combustion chambers to the-.draft`creating device, and the heat thus radiated is absorbed by the goodspassing through the heating up zone of the kiln. In this type of kilnthere is, in general, Vmorel heat remaining in the products ofSpecification of Letters Patent.

invention' is to creating devicefsuch as an exhaust fan or A To avoid a,too 'rapidvheating of the goods,

very undesirable with certainl classes of goods, it-has been thepractice to make the heating upv Zone' longer than would be other wisenecessary to retard the rapid heating up ofthe goods, and aspecific'object of they Patented Feb. l0, 1920. Application ined May as,1919. v seriaivNo. 300,445.'

present invention is to provide simple and effective means whereby theslow and gradual heatingl up of the goods may beobtained with aV heatingup zone of shorter length than has heretofore been employed. Toaccomplish this' I provide means whereby the temperature of the gaseousproducts in the conduits passing through the heating up zone maybereduced.

The various features of noveltyy which with particularity in theclaimsvannexedtol and forming a part Iof 'this specification.

For a better understanding of the invention, however, and theadvantagespossesse'd by 'it reference should be'had to the accompanyingdrawings and descriptive matter in which' I have illustrated anddescribed a preferred embodiment of my4 invention.'

Of the drawings:

Figure 1 is'a plan in section on the` line the well known Dressler type.In the' kiln shown, A represents the kiln chamber proper, and B the antechamber at the entrance or head end of thekiln. Track rails C areprovided a't the bottom of the chamber forthe `goods carrying cars L,and benches D are provided at the sides of the track on which aremounted the combustion chambers E. Each combustion chamber E isconnected,

- at'the junction lbetween the heating'up and draft creating device,shown in the drawings ber E. The goods carrying cars L comprise carbodies fitting closely between the `benches D and thereby protected inalarge measure from the high temperatures prevailing in the upperportion of the kiln chamber. goods N mounted on the cars pass up betweenthe two combustion chambers E and sets of conduits G to a lleveladjacent that of the top 'ot the kiln chamber. It will be understoodthat in operation, fuel,usually gas, is burned in the combustionchambers which are of suitably refractory material,Y

and the gaseous products of combustion are carried out of the combustionchambers through the conduits G bythe stacksuc-- tion. In so far asabove described the apparatus shown contains nothing now novel Withiiie.

The means which I have shown infthe drawings for "lowering theI heatradiatingcapacity. of .the conduit Gr in accordance with the presentinvention comprises means for admixing with the waste products ofcombustion leaving the combustion chambers, a'cooling agent such asatmospheric air. For this purpose I provide tubular inlets M leadingthrough the side Walls ofthe kiln chamber into the junction boxes orheaders F. 'As shown these tubular inlets are the form of iron pipeslocated in ports A1` formed in .the vmasonry structure of the kiln andeach having an'internal diameter substantially greater than the externaldiameter of the corresponding pipe M so that there is a capacity foradjustment of the.- iiilets M lengthwise. of `the tunnel as thecombustion chambers E and conduits Gr elongate' and shorten as withtemperature variations. The space between the inner walls ot the ports Mand the outer walls of the inlet pipes M may be luted with clay 'or thelike to prevent the leakage of air into the kilnl chamber proper.Advantageously the inlet pipes M are provided with dampers ort-hrottli'ng devices M1 whereby the amount of air drawn into thejunction boxes or headers F through the pipes M may be varied to meetditferentoperating conditions.

With the arrangement described the maximum temperature-of the conduits Gand thereby the effective heat radiatingcapacity of these conduits is'reduced by the admission of atmospheric air to the headers F throughthe inlet pipes M. In consequence it is possible to obtain a.sufficiently gradual heating up of the goods passing through the heatingup zone with a shorter length, of heating up zone than has heretoforebeen required.

weones day of May While in accordance with the provisions 'of thestatutes I have illustrated and described vthe best embodiments of myinvention now known to me, it Will be apparent to those skilled in theart that changes may be made inthe .form of' apparatus disclosed withoutdeparting from the spirit of my invention as set. forth and that undersome conditions certain features of my invention may be used toadvantagewithout the correspondinguseof other features.

Having nowdescribed ymy invention, what I claim as new;v and desire tosecure by Iletters Patent, is:

l. In a tunnel kiln comprising-a high' temperature zone'and'. aheatingup Zone bettween the high temperature Zone and. the goods entrance end'of the kiln and having' a combustion chamber space in the high temspacepassing through said heating up Zone,

said chamber and extension space being separated from the kiln chamberproper by heat .conducting walls, the .improvement which consists in -anair inlet to sald extension space. f

3. In a tunnel kiln `comprising' a high temperature zone and a heatingup Zone between the high temperature zone and the goods entrance end ofthe kiln and rhaving I a combustion chamberspace in the 'hight'ennperature zone and an extension of said .space passing through saidheating up Zone,

said chamber and extension space being separated from the kiln chamberproper by heat conducting walls, the improvement which consists in -aregulable air inlet tol said extension vspace'.

4. In atunnel kiln comprising a high temperature zone and .a heating upzone between the high temperature zone andthe goods entrant-eend yofthekiln and having a combustion chamber in the high temperature sione and aconduit extensiony thereof passing through said heating up zone, theimprovement which consists in an airinlet to said conduit adjacent itsconnection to the combustion chamber. f Signed at city of Zanesville, inthe county ot Muskingum and State of Ohio this 19th PHILIP DH. DRESSLER.

